A display device including a gray scale storage display element such as an electrophoresis element has attracted attention as one of display devices that can be driven with low power consumption. The display device has an advantage in that images can be held without power supply, whereby it is expected that the display device will be applied to an electronic book reader, a poster, or the like.
Display devices including various kinds of gray scale storage display elements have been proposed. For example, an active matrix display device formed using a transistor as a switching element of a pixel as in a liquid crystal display device or the like has been proposed (e.g., see Patent Document 1).
Further, a variety of driving methods of the display device has been proposed. For example, the following image switching method has been proposed: before images to be obtained are displayed, an entire display portion is converted into a first gray scale (e.g., white), which is sequentially converted into a second gray scale (e.g., black) when images are switched (e.g., see Patent Document 2).